I had this issue with my original sheet. I started with 2:1 and switched to 3:1 after three months of use. I replaced the sheet at four months with 6mm Marlow xls racing line. The marlow line has not frayed anywhere over eight months of hard sailing. In fact, it still looks brand new.In my opinion, nothing is wrong with the boat, it's just a light duty sheet for light duty sailing. If you want to sail the slop, then you need to start replacing the weak links.

Although a lot of attention seemed to be looking for a physical cause, there was not much mentioned at the time that "fraying of the main sheet" was more likely related to how we trim our sails. The general conclusion was that fraying:

Seemed to located in the same area about, 4'-6' around the Harken Cam Cleat.Was not the angle of how the line went through the cleat and would not be helped by installing a fairlead.Was not caused by the screws on the chafe plate or anything related to the stern cheek block. Was unaffected by the 3:1 or 2:1 ratio.Might have something to do with "stress or load" on the line..... Hummmm

Fast forward: Interesting that this topic has renewed activity. However, other than replacement and or upgrading ones lines, not much seems to have been uncovered as to the route cause of the problem or how to reduce it from happening.

Here's what I think is going on:A while ago I had a friends TI in my shop for some upgrades. We happen to notice that his main sheet was badly frayed (like the ones pictured in this post) and looked much worse than mine.... But I sailed more than he did. Same boat, same set up etc. So that made me curious...

Turns out my friend was in the habit of trimming his sail with the main sheet running directly through and in the Harken Cams while there was a load on the line.

I generally lift or "pop" the line out of the cams, and then trim my sail. Although this is not always possible to do, (especially when there's a heavy strain on the line), my main sheet was not as frayed as his.

It seems to me that by comparison, our different ways of trimming our sails had a direct effect on how much fraying our main sheets had.

I think you might be onto something there. I had a nine hour sail yesterday, and while my sheet is not showing any signs of fraying, I was paying attention because of this thread, and yes, it is easy to find yourself pulling in the sheet through the teeth while under load, rather than lifting it out of the teeth and dropping in down when trimming is complete.

...... it is easy to find yourself pulling in the sheet through the teeth while under load, rather than lifting it out of the teeth and dropping in down when trimming is complete.

"Teeth" Yes that's the word exactly! I was trying to think of something better than the "cams", to describe what I think is causing the fraying. But your right, the cams do have little teeth on them - Thanks .

I had this issue with my original sheet. I started with 2:1 and switched to 3:1 after three months of use. I replaced the sheet at four months with 6mm Marlow xls racing line. The marlow line has not frayed anywhere over eight months of hard sailing. In fact, it still looks brand new.In my opinion, nothing is wrong with the boat, it's just a light duty sheet for light duty sailing. If you want to sail the slop, then you need to start replacing the weak links.

I had this issue with my original sheet. I started with 2:1 and switched to 3:1 after three months of use. I replaced the sheet at four months with 6mm Marlow xls racing line. The marlow line has not frayed anywhere over eight months of hard sailing. In fact, it still looks brand new.In my opinion, nothing is wrong with the boat, it's just a light duty sheet for light duty sailing. If you want to sail the slop, then you need to start replacing the weak links.

Cheers,

J

Kayakman

do you remember how long your 3:1 sheet line was / is?

cc

Cci used the same length as the original sheet plus a couple of feet. Still its possible to figure how long a sheet you will need for the new 3:1 setup. Using the normal 2:1 setup, run the sheet to the bitter end at each cam, measure the distance between the two pulleys ( double and single ), double this, and add it to the length of the original sheet.